Re: [ietf-smtp] broken signatures, was Curious

Brandon Long <> Tue, 21 July 2020 20:35 UTC

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From: Brandon Long <>
Date: Tue, 21 Jul 2020 13:35:29 -0700
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To: John Levine <>
Cc: ietf-smtp <>
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Subject: Re: [ietf-smtp] broken signatures, was Curious
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On Tue, Jul 21, 2020 at 1:19 PM John Levine <> wrote:

> In article <>
> you write:
> >As useless mail headers do make emails heavier, I am in favour of
> >removing DKIM-Signature headers, that are known to be broken, e.g.
> >because the current host has modified (and resubmitted) the message.
> The amount of bandwidth used by e-mail is a rounding error of the
> Internet's total, which is mostly video these dayts, and the amount
> used by broken headers is a rounding error on that rounding error.
> Look at the headers of the mail in your inbox, particularly mail from
> large providers, and you'll find megabytes of headers that nobody is
> ever likely to look at or use.  This battle was over decades ago.

A better (but annoying) reason is there are a smattering of servers which
reject messages
based on broken DKIM signatures, against the rfc.